It is actually kinda hard problem. Anything a ship going away would drop would continue to move at speed it was dropped. And then if you are doing whole speed up and slow down they might even overshoot...
You could keep launching them from solar system. But well might need lot of them.
It really does get complicated when you start thinking of details and how mechanics work.
If you shoot something back at the same speed you're traveling to keep it "stationary", that's just called propulsion!
I feel like there might be slight issues on accelerating anything to same speed at interstellar distances inside distance of spaceship... You know equivalent gforces and that...
It shouldn't be that hard. It's basically just a network of satellites with directional antennas - tech we already have.
True, a series of huge relays getting towed out in each direction you want to go. Last time I read into it they talked about near moon or planet sized communication systems.